SWI-Prolog and the Web

Where Prolog is commonly seen as a component in a Web application that is either embedded or communicates using a proprietary protocol, we propose an architecture where Prolog communicates to other components in a Web application using the standard HTTP protocol. By avoiding embedding in external Web servers development and deployment become much easier. To support this architecture, in addition to the transfer protocol, we must also support parsing, representing and generating the key Web document types such as HTML, XML and RDF. This paper motivates the design decisions in the libraries and extensions to Prolog for handling Web documents and protocols. The design has been guided by the requirement to handle large documents efficiently. The described libraries support a wide range of Web applications ranging from HTML and XML documents to Semantic Web RDF processing. To appear in Theory and Practice of Logic Programming (TPLP)Comment: 31 pages, 24 figures and 2 tables. To appear in Theory and Practice of Logic Programming (TPLP

Matrix I

Prolog is an excellent tool for representing and manipulating data written in formal languages as well as natural language. Its safe semantics and automatic memory management make it a prime candidate for programming robust Web services. Where Prolog is commonly seen as a component in a Web application that is either embedded or communicates using a proprietary protocol, we propose an architecture where Prolog communicates to other components in a Web application using the standard HTTP protocol. By avoiding embedding in external Web servers development and deployment become much easier. To support this architecture, in addition to the transfer protocol, we must also support parsing, representing and generating the key Web document types such as HTML, XML and RDF. This paper motivates the design decisions in the libraries and extensions to Prolog for handling Web documents and protocols. The design has been guided by the requirement to handle large documents efficiently. The described libraries support a wide range of Web applications ranging from HTML and XML documents to Semantic Web RDF processing. The benefits of using Prolog for Web related tasks is illustrated using three case studies

Leadsto: A language and environment for analysis of dynamics by simulation

This article presents the language and software environment LEADSTO that has been developed to model and simulate dynamic processes in terms of both qualitative and quantitative concepts. The LEADSTO language is a declarative order-sorted temporal language, extended with quantitative notions like integer and real. Dynamic processes can be modelled in LEADSTO by specifying the direct temporal dependencies between state properties in successive states. Based on the LEADSTO language, a software environment was developed that performs simulations of LEADSTO specifications, generates data-files containing traces of simulation for further analysis, and constructs visual representations of traces. The approach proved its worth in a number of research projects in different domains

Automated Formal Analysis of Human Multi-Issue Negotiation Processes

Abstract. This paper reports on experiments in (human) multi-issue negotiation and their analysis, and presents a generic software environment supporting such an analysis. First, the paper presents a System for Analysis of Multi-Issue Negotiation (SAMIN). SAMIN is designed to analyse multi-issue negotiation processes between human negotiators, between human and software agents, and between software agents. The agents conduct one-to-one negotiations, in which the values across multiple issues are negotiated on simultaneously. To analyse such negotiation processes, the user can enter any formal property deemed useful into the system and use the system to automatically check this property in given negotiation traces. The paper presents the results of applying SAMIN in the analysis of empirical traces obtained from an experiment in multi-issue negotiation about second hand cars. In the experiment the efforts of 74 humans negotiating against each other have been analysed using SAMIN. 1

S.: Multi-concept alignment and evaluation

Abstract. In this paper we discuss a book annotation translation application scenario that requires multi-concept alignment – where one set of concepts is aligned to another set. Using books annotated by concepts from two vocabularies which are to be aligned, we explore two statistically-grounded measures (Jaccard and LSA) to build conversion rules which aggregate similar concepts. Different ways of learning and deploying the multi-concept alignment are evaluated, which enables us to assess the usefulness of the approach for this scenario. This usefulness is low at the moment, but the experiment has given us the opportunity to learn some important lessons.

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Abstract. Controlled vocabularies of various kinds (e.g., thesauri, classification schemes) play an integral part in making Cultural Heritage collections accessible. The various institutions participating in the Dutch CATCH programme maintain and make use of a rich and diverse set of vocabularies. This makes it hard to provide a uniform point of access to all collections at once. Our SKOS-based vocabulary and alignment repository aims at providing technology for managing the various vocabularies, and for exploiting semantic alignments across any two of them. The repository system exposes web services that effectively support the construction of tools for searching and browsing across vocabularies and collections or for collection curation (indexing), as we demonstrate.

Specification and Verification of Dynamics in Cognitive Agent Models

Within many domains, among which biological and cognitive areas, multiple interacting processes occur among agents with dynamics that are hard to handle. Current approaches to analyse the dynamics of such processes, often based on differential equations, are not always successful. As an alternative to differential equations, this paper presents the predicate logical Temporal Trace Language (TTL) for the formal specification and analysis of dynamic properties. This language supports the specification of both qualitative and quantitative aspects, and therefore subsumes specification languages based on differential equations. A software environment has been developed for TTL, that supports editing TTL properties and enables the formal verification of properties against a set of traces. The TTL environment proved its value in a number of projects within different domains. 1